阳江凹陷X油田珠江组低渗透储层特征及主控因素  

Characteristics and main controlling factors of low permeability reservoirs in Zhujiang Formation of Yangjiang sag X oilfield

作　　者：王华 戴建文 文鑫 马肖琳 郑伟 刘旭东 杨少春[2] WANG Hua;DAI Jianwen;WEN Xin;MA Xiaolin;ZHENG Wei;LIU Xudong;YANG Shaochun(Shenzhen Branch of CNOOC Ltd.(China),Shenzhen 518067,Guangdong,China;School of Geosciences,China University of Petroleum(East China),Qingdao 266580,Shandong,China)

机构地区：[1]中海石油(中国)有限公司深圳分公司,广东深圳518067 [2]中国石油大学(华东)地球科学与技术学院,山东青岛266580

出　　处：《世界地质》2023年第1期116-125,共10页World Geology

基　　金：国家自然科学基金面上项目(41772138)。

摘　　要：利用岩心观察、岩石样品测试、岩石镜下观察、扫描电镜和压汞测试等方法,对阳江凹陷X油田珠江组低渗透砂岩储层特征及主控因素进行了研究。结果表明,X油田珠江组低渗透储层以长石岩屑质石英砂岩为主,岩屑类型以酸性喷出岩、云母石英片岩为主,分选中等-较差;压实作用相对较弱,碳酸盐、泥质胶结作用强烈,产生于三角洲前缘沉积环境的大量泥晶碳酸盐胶结物、黏土矿物胶结物充填粒间孔隙,堵塞孔喉,导致砂岩低渗;普遍存在长石的溶蚀,但增孔、增渗不明显;孔隙类型以原生粒间孔为主,孔喉连通性较差;三角洲前缘沉积作用控制储层的岩石组分、颗粒结构、泥质杂基、碳酸盐来源及含量,碳酸盐、泥质胶结作用是导致储层低渗的关键因素。低渗透泥质砂岩纵向上分布在前三角洲厚层泥岩之间;低渗透钙质砂岩主要分布在大段泥岩与砂岩交界处,水下分流间湾泥岩为前缘沉积砂岩提供了碳酸盐物质来源。The characteristics and main controlling factors of the low permeability sandstone reservoirs in the Zhujiang Formation of Yangjiang sag X oilfield have been studied by core observation,rock sample test,rock microscopic observation,scanning electron microscope and mercury injection testing.The results show that the low permeability reservoirs in the Zhujiang Formation of X oilfield are mainly feldspar lithic quartz sandstone,of which the lithic types consist mainly of acidic eruptive rocks and mica quartz schists,with medium to poor separation.The compaction is relatively weak and the cementation of carbonate and argillaceous is strong.A large number of argillaceous carbonate cements and clay mineral cements produced in the delta front sedimentary environment fill intergranular pores,block pore throats,and lead to low permeability of sandstone.The dissolution of feldspar is widespread,but the porosity and permeability increasing are not obvious.Pore type is mainly primary intergranular pore,and pore throat connectivity is poor.The delta front sedimentation controls the rock composition,particle structure,argillaceous matrix,carbonate source and content of the reservoir.Carbonate and argillaceous cementation are the key factors leading to low permeability of the reservoirs.Low permeability argillaceous sandstone is vertically distributed among the thick mudstones of the prodelta facies.Low permeability calcareous sandstone is mainly distributed at the junction of large mudstone and sandstone.Underwater interdistributary bay mudstone provides carbonate material source for the delta front sedimentary sandstone.

关 键 词：低渗透储层 成岩特征 主控因素 阳江凹陷 X油田 珠江组 

分 类 号：P618.13[天文地球—矿床学]